1. Technical Field
The present invention relates to a projector.
2. Related Art
There is a known projector of related art including a light modulator that modulates light outputted from a light source apparatus in accordance with image information and a projection lens that projects the light modulated by the light modulator. As a projector of this type, to improve or otherwise change the contrast of a projected image, there is a known projector including a light control apparatus that shields part of the light outputted from the light source apparatus to adjust the amount of light incident on the light modulator. In the projector including the light control apparatus, when the light control apparatus shields a small amount of incident light, an optical element disposed on the light exiting side of the light control apparatus absorbs the light and hence generates heat, whereas when the light control apparatus shields a large amount of incident light, the light control apparatus absorbs the light and hence generates heat. In view of the situation described above, there is a proposed projector in which the flow rate of cooling air to be sent to the members described above is changed in accordance with the adjustment of the amount of light shielded by the light control apparatus (see JP-A-2010-224249, for example).
The projector described in JP-A-2010-224249 includes a light control apparatus, a polarization conversion element that is disposed on the light exiting side of the light control apparatus and optically converts incident light, a cooling fan, a duct that guides cooling air discharged from the cooling fan to the light control apparatus and the polarization conversion element, an open/close member, and a driver that drives the open/close member.
The projector described in JP-A-2010-224249 is so configured that the open/close member is driven to change the state of a delivery port of the duct, specifically, the degree of opening of the delivery port in such way that when the light control apparatus shields a large amount of light, the cooling air is delivered toward the light control apparatus, whereas when the light control apparatus shields a small amount of light, the cooling air is delivered toward the polarization conversion element.
The technology described in JP-A-2010-224249, however, requires the open/close member and the driver that drives the open/close member, undesirably resulting in an increase in the number of parts and an increase in the size of the projector because the open/close member and the driver are accommodated therein. Further, since electric power that drives the driver is required, undesirably also resulting in an increase in electric power consumed by the projector.